According to the U.S. Geological Survey website, tectonic plates are massive, irregular-shaped slabs of solid rock, composed of oceanic and continental lithosphere. The continental crust is made up of lightweight minerals like feldspar and quartz, while the oceanic crust is made of heavier and dense
There are seven major tectonic plates on the planet that are further subdivided into dozens of smaller plates. Geologists do not always agree on how to subdivide the minor plates. Each plate is in motion relative to the other plates.
Plate tectonics is primarily caused by Earth's cooling mechanism, which generates convection currents in the planet's mantle that trigger slow but constant tectonic plate movement. This phenomena occurs on the boundaries of adjacent plates, which are classified as divergent, convergent and transform
Continental and oceanic are the two types of tectonic plates. Continental plates tend to be larger than oceanic and bear the majority of a continent's mass. Continental plates tend to be much thicker on average, but less dense.
Each continent is embedded onto plates, which are made from lithospheres - Earth's outermost layer. Because this layer is stronger than the underlying layer, it is able to move. Several forces encourage it to do this, which means Earth's landmass remains the same, but the location of continents shif
According to About.com, plate tectonics is the scientific theory that attempts to explain the movement of the Earth's lithosphere, which has formed the landscape features seen across the globe. It provides geology with a comprehensive theory that explains how the Earth works.
The movement of tectonic plates causes earthquakes when two plates that are in contact with each other move in opposite directions and release built-up stress. For example, one plate may move north, while the other may move south. Stress can build up to a significant amount while the plates are held
Tectonic plates shift as a result of the intense heat at the Earth's core, which causes molten rock in the mantle layer to rise, while cooler rock near the surface sinks back down. This is a process referred to as thermal convection.
Earth's tectonic plates move due to the movement of magma in the mantle underneath the crust. Extreme temperatures inside the planet's core cause a convection cycle in which hot magma rises to the surface and eventually sinks back toward the core as it cools.
Tectonic plates move at the rate of about 1 to 2 inches each year. Tectonic plates can move in various directions, causing them to collide at certain points on Earth and pull away at other points.